User blog comment:Derekoe/DmC Findings/@comment-775152-20120413065919/@comment-976055-20120413075958

Yeah, that seems consistent with what I remember in DMC4 (and I think 3). Even though the rank would disappear from the HUD, hitting an enemy brought it back up, and you'd still be at the most recent rank you achieved, unless you got hit, or significant events happened in the game.